Normally, yes. If it is really old, or was designed for a tub only, it MIGHT not contain the mandated anti-scald features. This is not good (but it probably has this feature). I would not install it unless it did, though. Sometimes there are two outlets, but one is plugged. You might be able to plug the lower one and use the upper one alone. If they are both open, you'll need to find a plug for the bottom one if you are only going to use it for a shower.